In new home construction, can a radiant barrier (foil adhered directly to roofing underlayment material) be used in conjunction with Icynene foam insulation? Can the foam be sprayed onto the surface of the foil coated underlayment material? If yes to the above two questions, then do you recommend closed-cell or open-cell foam?
The answer is no. If you spray the foam on the foil surface it will destroy the reflectivity of the radiant barrier.